Syphilis, leprosy, and human immunodeficiency virus coinfection: a challenging diagnosis.

The association between syphilis, leprosy, and human immunodeficiency virus (HIV) is not well documented, and the emergence of isolated cases raises the interest and indicates that this triple coinfection can occur. We report the case of a 42-year-old man from Rio de Janeiro, Brazil, who presented with erythematous papules on the trunk, back, and upper and lower extremities; an erythematous plaque on the upper abdomen; and an erythematous violaceous plaque on the right thigh with altered sensitivity. Laboratory investigation showed a reagent VDRL test (1:512) and positive test results for Treponema pallidum hemagglutination.